This invention relates in general to universal joint assemblies and in particular to a retainer for holding the bearings within a bearing cup of a universal joint assembly prior to assembly on a trunnion.
Universal joints are well known devices which provide a driving connection between two members adapted to rotate about non-aligned axes of rotation. Universal joints are widely used between rotatable drive shaft sections in vehicle drive train systems. A typical universal joint includes a cross having a central body portion with four cylindrical trunnions extending outwardly therefrom. The trunnions are oriented in a single plane and extend at right angles relative to one another. A hollow cylindrical bearing cup having a closed end is mounted on the end of each of the trunnions. A plurality of bearings, such as roller bearings or needle bearings, are provided between the outer cylindrical surface of a given trunnion and the inner cylindrical surface of the associated bearing cup to permit relative rotational movement therebetween. The bearing cups which are mounted on a first opposed pair of the trunnions can be connected to a first end yoke secured to an end of a first drive shaft section, while the bearing cups mounted on a second opposed pair of the trunnions can be connected to a second end yoke secured to an end of a second drive shaft section.
To assemble the bearing cup on the trunnion of the universal joint, the plurality of roller bearings are initially disposed within the bearing cup. The roller bearings are positioned about the inner cylindrical surface thereof, with the axial ends of the roller bearings being located adjacent to the closed end and the open end of the bearing cup. The roller bearings are not positively retained within the bearing cup prior insertion of the trunnion therein. To prevent the roller bearings from falling out of the bearing cup during assembly, it is known to apply a somewhat tacky grease material between the roller bearings and the inner cylindrical surface of the bearing cup. The tackiness of the grease material is usually sufficient to retain the roller bearings within the bearing cup until the trunnion is inserted therein.
However, in some instances, the bearing cup and roller bearings are assembled in a first location and shipped to a second location prior to being installed on the trunnion. In these instances, the tacky grease material has been found to be insufficient of itself to retain the roller bearings within the bearing cup during the relatively rough handling sometime encountered during shipment. To address this, it is also known in the art to retain the roller bearings within the bearing cup by providing washers or seals within the bearing cup at one or both axial ends of the roller bearings. Unfortunately, known structures of this type have required that close tolerances be maintained between the roller bearings, the trunnion, and the bearing cup to prevent restriction of the free rotational movement of the roller bearings during use. Accordingly, it would be desirable to provide an improved structure for retaining the bearings within the bearing cup prior to assembly on the trunnion which is simple and inexpensive in construction and assembly.